sleeve and axle multi-layer cylinder fit is applied in gauge change mechanism of a new type of high-speed gauge-changeable EMUs. In order to research deeply on the influence of fit value on contact pressure and structural stress, methods of elastic mechanics and finite element analysis were applied respectively, and the effect of several different fit value were analyzed. Results showed that: apart from the edge of contact region, the contact pressure between wheel and sleeve is positive linear to the interference fit value; Clearance fit value of sleeve and axle has significant effect on the inner surface of sliding sleeve, and the real clearance value is reduced by the compression effect of wheel and sleeve interference fit; it is suggested to take the compression effect into consideration when design the clearance fit value of wheel and sleeve.